Autozone carries remanufactured distributors that use a much improved reluctor/pickup/polepiece setup for around $120. Its a better design than GM used.

Add up of the cost of all the rebuild parts and you might not want to do do the labor. If you do the job yourself setting the shaft end play clearance is critical. As the distributor wears shaft slop results. You must have a set of shims to do this. When you rebuild you must recheck and adjust the end play. I would also replace all the internal parts and the module.
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87GT - 3800SC Series III engine, 3.4" Pulley, N* TB, LS1 MAF, Flotech Exhaust Autolite 104's Custom CAI 4T65eHD w. custom axles, HP Tuners VCM Suite.
87GT - 3.4L Turbocharged engine, modified TH125H
" I'M ON THE LOOSE WITHOUT THE JUICE "
[This message has been edited by Dennis LaGrua (edited 11-21-2008).]